Who contributed to the periodic table

After a laser bean passes through two thin parallel slits, thefirst completely dark fringes occur at ± 15.00with the original direction of the beam, as veiwed on a screen farfrom the slits.

When two forces or more forces act on an object, the forces are

If you shine a single light source on a screen you will see that the entire screen is lit up. Assume this light source is of a single frequency (color).

A 2.0-kg silverware drawer does not slide readily. The owner gradually pulls with more and more force, and when the applied force reaches 9.0 N, the drawer suddenly opens, throwing all the utensils to the floor.

A small ball of charge Q and mass m has a velocity v at infinity. It collides head-on with a ball of the same charge and mass which is initially at rest. What is the minimal distance between the charges during the collision?

Katie runs 6 km in 0.6 hour, then 5 km in 0.5 hour. Katie's average speed is __ per hour.

A derived unit is a combination of fundamental units. Which of the following is an example of a derived unit? a) centimeter (used to measure distance) b) gram (used to measure mass) c) cubic centimeter (used to measure volume)

Technician A says that a heater core leak can be the result of the coolant wearing a hole through the core. Technician B says that a core leak can be caused by chemical action eating a hole through the core. Who is correct?

If the Coast Guard warns of a giant wave of water approaching the shore as a result of a major earthquake, they are warning of a. an aftershock. b. liquefaction. c. a tsunami. d. landslides.

What is the total number of atoms in the following formula? CaBr2 4 3 2 1